Standing in the back yard myself and my best friend saw a bright light through his tree, we assumed it was a helicopter as that is common place here in calgary. the light moved into sight from beyond the tree and it was clear this bright light was not a helicopter or an aircraft we commonly see over calgary. The craft was silent and moved at a constant pace at low altitude, i know this because it flew below the cloud cover. we were stunned for a moment absorbing this event and my friend pulled out his phone to catch the event on video. as he raised the camera and it was like who ever was piloting this craft was watching us because it dimmed to nothing and vanished before we could catch it on tape.